Returns the change time for file (that is, the time directory information about the file was changed, not the file itself).
Note that on Windows (NTFS), returns creation time (birth time).
File.new("testfile").ctime #=> Wed Apr 09 08:53:14 CDT 2003
Returns the birth time for file.
File.new("testfile").birthtime #=> Wed Apr 09 08:53:14 CDT 2003
If the platform doesn’t have birthtime, raises NotImplementedError.
Returns the pathname used to create file as a string. Does not normalize the name.
The pathname may not point to the file corresponding to file. For instance, the pathname becomes void when the file has been moved or deleted.
This method raises IOError for a file created using File::Constants::TMPFILE because they don’t have a pathname.
File.new("testfile").path #=> "testfile" File.new("/tmp/../tmp/xxx", "w").path #=> "/tmp/../tmp/xxx"
Returns true if the named file exists and has a zero size.
file_name can be an IO object.
Returns true if the named file exists and has a zero size.
file_name can be an IO object.
Returns true if the named files are identical.
file_1 and file_2 can be an IO object.
open("a", "w") {} p File.identical?("a", "a") #=> true p File.identical?("a", "./a") #=> true File.link("a", "b") p File.identical?("a", "b") #=> true File.symlink("a", "c") p File.identical?("a", "c") #=> true open("d", "w") {} p File.identical?("a", "d") #=> false
With no associated block, File.open is a synonym for File.new. If the optional code block is given, it will be passed the opened file as an argument and the File object will automatically be closed when the block terminates. The value of the block will be returned from File.open.
If a file is being created, its initial permissions may be set using the perm parameter. See File.new for further discussion.
See IO.new for a description of the mode and opt parameters.
Returns the hash of available encoding alias and original encoding name.
Encoding.aliases
#=> {"BINARY"=>"ASCII-8BIT", "ASCII"=>"US-ASCII", "ANSI_X3.4-1968"=>"US-ASCII",
"SJIS"=>"Windows-31J", "eucJP"=>"EUC-JP", "CP932"=>"Windows-31J"}
Returns the previous exception ($!) at the time this exception was raised. This is useful for wrapping exceptions and retaining the original exception information.
Return the receiver associated with this KeyError exception.
Return the receiver associated with this NameError exception.
Return the arguments passed in as the third parameter to the constructor.
Return the receiver associated with this FrozenError exception.
Return this SystemCallError’s error number.
Returns the list of Modules nested at the point of call.
module M1 module M2 $a = Module.nesting end end $a #=> [M1::M2, M1] $a[0].name #=> "M1::M2"
In the first form, returns an array of the names of all constants accessible from the point of call. This list includes the names of all modules and classes defined in the global scope.
Module.constants.first(4) # => [:ARGF, :ARGV, :ArgumentError, :Array] Module.constants.include?(:SEEK_SET) # => false class IO Module.constants.include?(:SEEK_SET) # => true end
The second form calls the instance method constants.
Returns a list of modules included/prepended in mod (including mod itself).
module Mod include Math include Comparable prepend Enumerable end Mod.ancestors #=> [Enumerable, Mod, Comparable, Math] Math.ancestors #=> [Math] Enumerable.ancestors #=> [Enumerable]
Returns an array of the names of the constants accessible in mod. This includes the names of constants in any included modules (example at start of section), unless the inherit parameter is set to false.
The implementation makes no guarantees about the order in which the constants are yielded.
IO.constants.include?(:SYNC) #=> true IO.constants(false).include?(:SYNC) #=> false
Also see Module#const_defined?.
Returns the remainder from dividing by the value.
x.remainder(y) means x-y*(x/y).truncate
Returns the value raised to the power of n.
Note that n must be an Integer.
Also available as the operator **.